Actually crafting plot items should be off limits
The forge takes into account that you're using something that you're allowed to craft. It'll take into account the price of your artifact, therefore there is no need to cap it strictly because once you reach your 200k cap or whatever it is, it should then tell you to piss off.
Faction armour seems to be the only exception to the rule at present. Which is plot tagged. Try the same thing with a chainmail.
For now don't craft armour past +5 or anything past the value of 220k. If you want to check the cost of your item and get past the refresh bug, click on the 'interact' sign again. If you don't and you're found with an item which is obviously illegal then ignorance of this post will not be an excuse.
Weapons work as intended, as do trinkets etc, as far as I know.
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